A multi-channel transmit/receive radio frequency (RF) system for a magnetic resonance examination system is known from the paper ‘Comprehensive RF safety concept for parallel transmission MR’ in PIERS Proceedings, Cambridge, USA, Jul. 2-6, 2008 by I. Graesslin.
The known multi-channel transmit/receive radio frequency (RF) system comprises an RF antenna array, such as a multi-channel body coil or a (local) multi-element (RF) transmit array. A plurality of RF amplifiers is provided to individually activate the individual antenna elements of the RF antenna array. Further, pick-up coils are provided for each to the RF antenna elements. The electrical current of each pick-up element is monitored and compared with the demanded RF waveform. This enables to detect amplitude and phase deviations at the RF antenna elements and control local the specific absorption rate (SAR). The US patent application US2010/0167668 concerns monitoring a radiofrequency transmitter in a magnetic resonance tomography system.